Medical Review Officer (MRO) Selection

Every drug test result must be reviewed by a Medical Review Officer per § 40.121 before reporting. The MRO is the final gatekeeper on positive vs. negative determinations.

MRO qualifications

Per § 40.121:

• Licensed physician (Doctor of Medicine or Osteopathy)
• Knowledge of substance abuse disorders
• Knowledge of DOT drug testing regulations
• Continuing education (~12 hours every 3 years on DOT testing)
• Active medical license
• Not affiliated with the laboratory that performs the testing (independence)

What the MRO does

1. Reviews all positive, adulterated, substituted, invalid, and dilute test results
2. Conducts interview with driver before reporting positive (sometimes called the "MRO call")
3. Considers driver's medical explanation (prescription drugs, etc.)
4. Determines final test result
5. Reports the result to the carrier (or C/TPA)
6. Reports negative-dilute / refusal as MRO determines

When you need a dedicated MRO

• In-house testing program → need an MRO (usually contract)
• Working with a C/TPA → MRO is included
• Working with a single lab (e.g., Quest) → may have MRO services or you contract separately

Cost

• Per-test MRO fee: $15-35 per positive (most labs don't charge for negatives)
• Annual MRO retainer (smaller carrier): $300-600/year

Common red flags

• MRO does not interview drivers before reporting positives
• MRO is the same entity as the lab (conflict)
• MRO does not document medical explanations
• MRO reports results before completing review
• MRO has only "DOT exam" credentialing without substance-specific training

Verification

Before hiring an MRO, verify:

• Active medical license (state board)
• DOT training certification
• Liability insurance
• References from other motor carriers

Switching MROs

When changing MRO, the new MRO must:

• Receive all prior records (drug test history)
• Review any pending positive results
• Honor any in-progress follow-up testing schedules

CFR citations

• 49 CFR Part 40 Subpart G
• 49 CFR § 40.121
• 49 CFR § 40.123

How Compass surfaces this

This skill is searchable in the Compass Ask interface and runs against the carrier's actual fleet data when invoked from within the relevant tracker. It is read-only — no actions are taken without explicit user approval.

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